(1) Field of the Invention
The present invention relates to an oxygen gas cartridge, which can be used in medicine, to promote health, in a disaster, to light a torch and so on.
(2) Prior Art
As shown in FIG. 4, to prevent leakge of oxygen gas O out of a cartridge 11, an opening of a main body 14 of the cartridge 11 is sealed by a sealing plate 12 disposed between the main body 14 and a packing 16, made of rubber for example, by calking.
Such a cartridge as described above is likely to leak when the temperature rises or falls extremely or the packing becomes too old. Especially when it is under -30.degree. C., the calked area 19 is easily warped to allow gas leakage by difference of contraction rates of the metalic main body 14, the sealing plate 12 and the packing 16.
Electric welding of the sealing plate to the main body of a cartridge would secure much more complete sealing. Electric welding operation is, however, very dangerous, as the cartridge would explode easily because of the inner oxygen gas.